Optimization Study of Expansive Agents of Shrinkage-Compensating Concrete

2011 ◽  
Vol 250-253 ◽  
pp. 750-754 ◽  
Author(s):  
Qin Yong Ma ◽  
Wei Huang ◽  
Peng Bo Cui
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Portland Cement ◽  
Coarse Aggregate ◽  
Splitting Tensile Strength ◽  
Normal Concrete ◽  
Bonding Force ◽  
Reinforcing Effect ◽  
Optimization Study

Using 6% HCSA, HEA and CSA equivalent replacement Slag Portland Cement add into the normal concrete, the compressive strength, splitting tensile strength and flexural strength at the age of 3d, 7d and 28d are researched. It is concluded that reinforcing effect of the three expensive agents are in order CSA, HEA and HCSA form the view of mechanics , expansive agents increase the bonding force between coarse aggregate and slurry, alleviate the development speed of cracks and increase the destruction deformability of concrete.

scholarly journals Concrete Properties using Treated Recycled EPS

2021 ◽  
Vol 877 (1) ◽  
pp. 012028
Author(s):  
Hasan Jasim Mohammed ◽  
Yasir Gaib Hussein
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Silica Fume ◽  
Coarse Aggregate ◽  
Splitting Tensile Strength ◽  
The Other ◽  
Modulus Of Rupture ◽  
Normal Concrete ◽  
Concrete Properties

Abstract The study explores the mechanical properties of treated recycled extended polystyrene (TEPS) concrete, treated by two methods, one by heating, and the other by immersed recycled EPS in cement neat. By substituting 0 %, 15 %, 25 %, and 35 % of the coarse aggregate volume with treated recycled EPS, (for both method). Treated recycled TEPS concrete ratios are experimentally prepared, while the cement is substituted thru 10 % silica fume (SF). Tests were carried out, like compressive strength, splitting tensile strength, modulus of rupture, and density. The outcomes display the decreasing of the compressive strength, tensile strength and modulus of rupture of TEPS concretes with rise TEPS percentage around 26 %, 17 % and 32 %, respectively (35% TEPS) related to standard concrete. They also show that TEPS concrete density decrease about 30 % of normal concrete. The TEPS is suitable in concrete and meets provisions.

scholarly journals Some properties of sustainable concrete containing two environmental wastes

2018 ◽  
Vol 162 ◽  
pp. 02029
Author(s):  
Wasan Khalil ◽  
Nazar Al Obeidy
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Glass Powder ◽  
Coarse Aggregate ◽  
Plastic Waste ◽  
Splitting Tensile Strength ◽  
Partial Substitution ◽  
Dry Density ◽  
Sustainable Concrete

This investigation includes the use of 15% of glass wastes as a partial substitution to cement in combination with plastic wastes as volumetric replacement to natural coarse aggregate to produce sustainable concrete. Different volumetric replacements of plastic waste to natural coarse aggregate (25%, 50%, 75%, and 100%) were used in concrete containing 15% glass powder as a replacement by weight of cement. Generally, the results show that the inclusion of 15% glass powder improves the compressive strength, splitting tensile strength and flexural strength by about 13.3%, 36.3%, and 34.7%respectively at 60 day age in comparison with reference concrete without wastes, also the results show a decrease in water absorption and an increase in dry density. The inclusion of plastic waste aggregate in the presence of 15% glass powder leads to a decrease in the compressive strength, flexural strength, splitting tensile strength, dry density, ultrasonic pulse velocity, and thermal conductivity. The percentage reductions are 59.8%, 46.3%, 43.6%, 20.5%, 28.6%, and 54.4% respectively for concrete specimens that including 100% plastic waste coarse aggregate in comparison with concrete specimens without plastic waste aggregate.

scholarly journals PERFORMANCE OF HIGH STRENGTH LIGHTWEIGHT CONCRETE USING PALM WASTES

2018 ◽  
Vol 19 (2) ◽  
pp. 30-42
Author(s):  
Md. Nazmul Huda ◽  
Mohd Zamin Jumaat ◽  
A. B. M. Saiful Islam ◽  
Walid A. Al-Kutti
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Coarse Aggregate ◽  
Lightweight Concrete ◽  
High Strength ◽  
Splitting Tensile Strength ◽  
Palm Shell

The performance of high strength structural lightweight concrete (LWC) using the palm wastes, oil palm shell (OPS) as well as palm oil clinker (POC) has been reported. Existing literatures used either OPS or POC individually for production of LWC. Each concept has their own advantages-disadvantages. In this study, both OPS and POC have been put together as coarse aggregate on the way to see the improvement of mechanical properties of waste based LWC. To achieve this purpose, regular coarse aggregate has been fully replaced by OPS and POC in the concrete. This structural grade lightweight concrete is named as palm shell and clinker concrete (PSCC). Attempts have been made with the series of OPS and POC mixture aimed at identifying for better performance. The quantity of OPS and POC mix has been varied as 30%, 40%, 50%, 60% and 70%. Mechanical properties of PSCC like density, workability, compressive strength at different ages, flexural strength, splitting tensile strength as well as modulus of elasticity have been evaluated. It is revealed that the proposed PSCC has extensive potential in terms of high compressive strength and good material behavior to perform as a better LWC. The study could offer structural lightweight concrete of compressive strength up to 46 MPa that is 31% higher than the control mix. The usage of 50% OPS to 50% POC coarse aggregate by vol. in the concrete mix is found to be the optimum mix. Furthermore, simple correlations have been developed which can easily predict compressive strength, splitting tensile strength, flexural strength, modulus of elasticity and ultrasonic pulse velocity of lightweight concrete.

Effect of using magnetic water on the mechanical properties of concrete exposed to elevated temperature

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Wasim Barham ◽  
Ammar AL-Maabreh ◽  
Omar Latayfeh
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Elevated Temperature ◽  
Flexural Strength ◽  
Tap Water ◽  
Splitting Tensile Strength ◽  
Content Type ◽  
Normal Water ◽  
Magnetic Water

PurposeThe influence of using magnetic water instead of tap water in the mechanical properties of the concrete exposed to elevated temperatures was investigated. Two concrete mixes were used and cast with the same ingredients. Tap water was used in the first mix and magnetic water was used in the second mix. A total of 48 specimens were cast and divided as follows: 16 cylinders for the concrete compressive strength test (8 samples for each mix), 16 cylinders for the splitting tensile strength (8 specimens for each mix) and 16 beams to test the influences of magnetized water on the flexural strength of concrete (8 specimens for each mixture). Specimens were exposed to temperatures of (25 °C, 200 °C, 400 °C and 600 °C). The experimental results showed that magnetic water highly affected the mechanical properties of concrete. Specimens cast and curried out with magnetic water show higher compressive strength, splitting tensile strength and flexural strength compared to normal water specimens at all temperatures. The relative strength range between the two types of water used was 110–123% for compressive strength and 110–133% for splitting strength. For the center point loading test, the relative flexural strength range was 118–140%. The use of magnetic water in mixing concrete contribute to a more complete hydration process.Design/methodology/approachExperimental study was carried out on two concrete mixes to investigate the effect of magnetic water. Mix#1 used normal water as the mixing water, and Mix#2 used magnetic water instead of normal water. After 28 days, all the samples were taken out of the tank and left to dry for seven days, then they were divided into different groups. Each group was exposed to a different temperature where it was placed in a large oven for two hours. Three different tests were carried out on the samples, these tests were concrete compressive strength, flexural strength and splitting tensile strength.FindingsExposure of concrete to high temperatures had a significant influence on concrete mechanical properties. Specimens prepared using magnetic water showed higher compressive strength at all temperature levels. The use of magnetic water in casting and curing concrete can increase the compressive strength by 23%. Specimens prepared using magnetic water show higher splitting tensile strength at all temperatures up to 33%. The use of magnetic water in casting and curing can strengthen and increase concrete resistance to high temperatures, a significant enhancement in flexural strength at all temperatures was found with a value up to 40%.Originality/valuePrevious research proved the advantages of using magnetic water for improving the mechanical properties of concrete under normal conditions. The potential of using magnetic water in the concrete industry in the future requires conducting extensive research to study the behavior of magnetized concrete under severe conditions to which concrete structures may be subjected to. These days, there are attempts to obtain stronger concrete with high resistance to harsh environmental conditions without adding new costly ingredients to its main mixture. No research has been carried out to investigate the effect of magnetic water on the mechanical properties of concrete exposed to elevated temperature. The main objective of this study is to evaluate the effect of using magnetic water on the mechanical properties of hardened concrete subjected to elevated temperature.

scholarly journals Effect of Recycled Coarse Aggregates in Properties of Concrete

2008 ◽  
Vol 3 (4) ◽  
pp. 130-137 ◽  
Author(s):  
R Kumutha ◽  
K Vijai
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Modulus Of Elasticity ◽  
Coarse Aggregate ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Split Tensile Strength ◽  
Coarse Aggregates ◽  
The Cost

The properties of concrete containing coarse recycled aggregates were investigated. Laboratory trials were conducted to investigate the possibility of using recycled aggregates from the demolition wastes available locally as the replacement of natural coarse aggregates in concrete. A series of tests were carried out to determine the density, compressive strength, split tensile strength, flexural strength and modulus of elasticity of concrete with and without recycled aggregates. The water cement ratio was kept constant for all the mixes. The coarse aggregate in concrete was replaced with 0%, 20%, 40%, 60%, 80% and 100% recycled coarse aggregates. The test results indicated that the replacement of natural coarse aggregates by recycled aggregates up to 40% had little effect on the compressive strength, but higher levels of replacement reduced the compressive strength. A replacement level of 100% causes a reduction of 28% in compressive strength, 36% in split tensile strength and 50% in flexural strength. For strength characteristics, the results showed a gradual decrease in compressive strength, split tensile strength, flexural strength and modulus of elasticity as the percentage of recycled aggregate used in the specimens increased. 100% replacement of natural coarse aggregate by recycled aggregate resulted in 43% savings in the cost of coarse aggregates and 9% savings in the cost of concrete.

scholarly journals PENGARUH PENGGUNAAN TANAH MEDITERAN SEBAGAI BAHAN SUBSTITUSI SEMEN TERHADAP KUAT TEKAN DAN TARIK BETON

2020 ◽  
Vol 5 (2) ◽  
pp. 59-71
Author(s):  
Sri Devi Nilawardani
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Coarse Aggregate ◽  
Comparative Method ◽  
Fine Aggregate ◽  
Main Ingredient ◽  
Normal Concrete ◽  
Long Run ◽  
Cement Manufacture ◽  
Initial Idea

Title: The Effect of Using Mediteran Soil as Cement Substitution Materials in Compressive Strength and Tensile Strength of Concrete Concrete is a composite material (mixture) of cement, fine aggregate, coarse aggregate, and water. The potential of limestone in Indonesia is very large, reaching 28.678 billion tons which is the main ingredient in the cement manufacture. In the long run it will be depleted because it is a non-renewable natural resources. So to reduce the use of limestone the utilization of Mediteran soil as a substitution for some cement in the manufacture of concrete is required. The initial idea is based on the chemical composition contained in the Mediteran soil almost identical to the cement, which is carbonate (CaO) and silica (SiO2). The purpose of this research is to reveal the influence of substitution of Mediteran soil by 20% and 40% in the compressive strength and tensile of the concrete at age 3, 7, 14, and 28 days with the number of test specimen each 3 pieces on each variation in 10cm x20cm cylinder with planning of concrete mixture refers to SK SNI method T-15-1900-03. The type of research used is quantitative with the experimental method of laboratory test and data analysis of comparative method and regression. The results show that compressive strength and tensile strength of concrete using Mediteran soil substitution comparable to  the strength of normal concrete with dry treatment. In the composition of 20% Mediteran soils decreased by 51.35% or 7.9 MPa (compressive strength) and 30.60% or 0.93 MPa (tensile strength). While the composition of 40% Mediteran soil decreased by 43.78% or 9.13 MPa (compressive strength) and 2.24% or 1.31 MPa (tensile strength).  

scholarly journals The Effect of Nano Metakaolin Material on Some Properties of Concrete

2013 ◽  
Vol 6 (1) ◽  
pp. 50-61
Author(s):  
Amer M. Ibrahem ◽  
Shakir A. Al-Mishhadani ◽  
Zeinab H.Naji
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Portland Cement ◽  
Water Absorption ◽  
Thermal Activation ◽  
Ordinary Portland Cement ◽  
Splitting Tensile Strength ◽  
Kaolin Clay ◽  
Cement Ratio ◽  
Water Cement Ratio

This investigation aimed to study the effect of nano metakaolin ( NMK ) on some properties (compressive strength ,splitting tensile strength & water absorption ) of concrete. The nano metakaolin (NMK) was prepared by thermal activation of kaolin clay for 2 hours at 750 Ċ. The cement used in this investigation consists of ordinary Portland cement (OPC). The OPC was partially substituted by NMK of ( 3, 5 & 10%) by weight of cement. The C45 concrete was prepared , using water/cement ratio ( W/c) of (0.53) .The Water absorption was tested at 28 days while the tests (compressive strength ,splitting tensile strength) were tested at ages of (7, 28, 60,& 90) days . The compressive strength and splitting tensile strength of concrete with NMK were higher than that of reference concrete with the same W/c ratio.The improvement in the compressive strength when using NMK was (42.2, 55.8 , 63.1% ) at age 28 days for ( 3%, 5%, &10% ) replacement of NMK respectively whereas the improvement in the splitting tensile strength was (0% , 36% & 46.8 %) at age of 28 days when using (3%, 5%, &10% ) NMK respectively. The improvement in the water absorption was (16.6%, 21.79%, &25.6 ) when using (3, 5, &10% )NMK.

scholarly journals Physical Properties of Concrete Containing Graphene Oxide Nanosheets

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1707 ◽  
Author(s):  
Yu-You Wu ◽  
Longxin Que ◽  
Zhaoyang Cui ◽  
Paul Lambert
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Graphene Oxide ◽  
Flexural Strength ◽  
Portland Cement ◽  
Physical Properties ◽  
Ordinary Portland Cement ◽  
Construction Materials ◽  
Split Tensile Strength ◽  
Cement Pastes

Concrete made from ordinary Portland cement is one of the most widely used construction materials due to its excellent compressive strength. However, concrete lacks ductility resulting in low tensile strength and flexural strength, and poor resistance to crack formation. Studies have demonstrated that the addition of graphene oxide (GO) nanosheet can effectively enhance the compressive and flexural properties of ordinary Portland cement paste, confirming GO nanosheet as an excellent candidate for using as nano-reinforcement in cement-based composites. To date, the majority of studies have focused on cement pastes and mortars. Only limited investigations into concretes incorporating GO nanosheets have been reported. This paper presents an experimental investigation on the slump and physical properties of concrete reinforced with GO nanosheets at additions from 0.00% to 0.08% by weight of cement and a water–cement ratio of 0.5. The study demonstrates that the addition of GO nanosheets improves the compressive strength, flexural strength, and split tensile strength of concrete, whereas the slump of concrete decreases with increasing GO nanosheet content. The results also demonstrate that 0.03% by weight of cement is the optimum value of GO nanosheet dosage for improving the split tensile strength of concrete.

Influence the Carbonation Resistance and Mechanical Properties of Shotcrete by Accelerated Carbonation Test

2014 ◽  
Vol 1065-1069 ◽  
pp. 1985-1989
Author(s):  
Jia Bin Wang ◽  
Di Tao Niu ◽  
Rui Ma ◽  
Ze Long Mi
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Steel Fiber ◽  
Splitting Tensile Strength ◽  
Construction Technology ◽  
Accelerated Carbonation ◽  
Carbonation Depth ◽  
Normal Concrete ◽  
Carbonation Resistance

In order to investigate the carbonation resistance of shotcrete and the mechanical properties after carbonation, the accelerated carbonation test was carried out. The results indicate that the carbonation resistance of shotcrete is superior to that of normal concrete. With the increasing of carbonation depth, compressive strength and splitting tensile strength of shotcrete grew rapidly. The admixing of steel fiber can further improve the carbonation resistance, reduce the carbonation rate, and increase the splitting tensile strength of shotcrete greatly. Besides, based on analyzing the effects of construction technology and steel fiber of concrete for the carbonation resistance, a carbonation depth model for shotcrete was established. Key words: shotcrete; carbonation; steel fiber; mechanical properties

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